Introduction to the Eye

Welcome to the introduction to the eye. The video provided below by Medinaz provides a very detailed yet explanation of eye structures, parts of the eye/eyeball and its function.

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Parts of the Eye

"Aqueous humor: The fluid produced in the eye.

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Bruch's membrane: Located in the retina between the choroid and the retinal pigmented epithelium (RPE) layer; provides support to the retina and functions as the 'basement' membrane of the RPE layer.

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Ciliary body: Part of the eye, above the lens, that produces the aqueous humor. Choroid: Layer of the eye behind the retina, contains blood vessels that nourish the retina.

 

Cones: The photoreceptor nerve cells present in the macula and concentrated in the fovea (the very center of the macula); enable people to see fine detail and color.

 

Cornea: The outer, transparent structure at the front of the eye that covers the iris, pupil and anterior chamber; it is the eye's primary light-focusing structure.

 

Drusen: Deposits of yellowish extracellular waste products that accumulate within and beneath the retinal pigmented epithelium (RPE) layer.

 

Fovea: The pit or depression at the center of the macula that provides the greatest visual acuity.

 

Iris: The colored ring of tissue behind the cornea that regulates the amount of light entering the eye by adjusting the size of the pupil.

 

Lens: The transparent structure suspended behind the iris that helps to focus light on the retina; it primarily provides a fine-tuning adjustment to the primary focusing structure of the eye, which is the cornea.

 

Macula: The portion of the eye at the center of the retina that processes sharp, clear straight-ahead vision. Optic nerve: The bundle of nerve fibers at the back of the eye that carry visual messages from the retina to the brain.

 

Photoreceptors: The light-sensing nerve cells (rods and cones) located in the retina.

 

Pupil: The adjustable opening at the center of the iris through which light enters the eye.

 

Retina: The light-sensitive layer of tissue that lines the back of the eye.

 

Retinal Pigmented Epithelium (RPE): A layer of cells that protects and nourishes the retina, removes waste products, prevents new blood vessel growth into the retinal layer and absorbs light not absorbed by the photoreceptor cells; these actions prevent the scattering of the light and enhance the clarity of vision.

 

Rods: Photoreceptor nerve cells in the eyes that are sensitive to low light levels and are present in the retina, but outside the macula.

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Sclera: The tough outer coat that protects the entire eyeball.

 

Trabecular meshwork: Spongy tissue located near the cornea through which aqueous humor flows out of the eye. Vitreous: Clear jelly-like substance that fills the eye from the lens to the back of the eye."